 |
» |
|
|
|
Debug only Privileged Mode: MA, MD, MCS, MZ, MSEC Modifies the contents of the specified number of words at the specified address. Syntax | |
MA offset [count] [base] [newvalue(s)] ABS relative
MD dst.off [count] [base] [newvalue(s)] Data segment
MDB offset [count] [base] [newvalue(s)] DB relative
MS offset [count] [base] [newvalue(s)] S relative
MQ offset [count] [base] [newvalue(s)] Q relative
MC logaddr [count] [base] [newvalue(s)] Program file (default)
MCG logaddr [count] [base] [newvalue(s)] Group library
MCP logaddr [count] [base] [newvalue(s)] Account library
MCLG logaddr [count] [base] [newvalue(s)] Logon group
MCLP logaddr [count] [base] [newvalue(s)] Logon account
MCS logaddr [count] [base] [newvalue(s)] System library
MCU fname logaddr [count] [base] [newvalue(s)] User library
MCA cmabsaddr [count] [base] [newvalue(s)] Absolute CST
MCAX cmabsaddr [count] [base] [newvalue(s)] Absolute CSTX
MV virtaddr [count] [base] [newvalue(s)] Virtual
MZ realaddr [count] [base] [newvalue(s)] Real memory
MSEC ldev.off [count] [base] [newvalue(s)] Secondary store
|
By default, the current value is displayed. The ENV variable
QUIET_MODIFY can be used to suppress the display of the
current value. Parameters | |
- offset
MA, MDB, MQ, MS only. The CM word offset that specifies the relative starting location of the area to be modified. - logaddr
MC, MCG, MCP, MCLG, MCLP, MS, MCU only. A full logical code address (LCPTR) specifies three necessary items: The logical code file (PROG, GRP, SYS, and so on.). NM: the virtual space ID number (SID). CM: the logical segment number. NM: the virtual byte offset within the space. CM: the word offset within the code segment.
Logical code addresses can be specified in various levels of detail: As a full logical code pointer (LCPTR): - MC procname+20
Procedure name lookups return LCPTRs. - MC pw+4
Predefined ENV variables of type LCPTR. - MC SYS(2.200)
Explicit coercion to a LCPTR type.
As a long pointer (LPTR): - MC 23.2644
sid.offset or seg.offset
The logical file is determined based upon the command suffix. For example: MCS implies SYS, and so on
As a short pointer (SPTR): For NM, the short pointer offset is converted to a long pointer using the function STOLOG, which looks up the SID of the loaded logical file. This is different from the standard short to long pointer conversion, STOL, which is based on the current space registers (SRs). For CM, the current executing logical segment number and the
current executing logical file are used to build a LCPTR.
The search path used for procedure name lookups is based on the
command suffix letter: - MC
Full search path:
NM: PROG, GRP, PUB, USER(s), SYS CM: PROG, GRP, PUB, LGRP, LPUB, SYS
- MCG
Search GRP, the group library. - MCP
Search PUB, the account library. - MCLG
Search LGRP, the logon group library. - MCLP
Search LPUB, the logon account library. - MCS
Search SYS, the system library. - MCU
Search USER, the user library.
For a full description of logical code addresses, refer to the section
"Logical Code Addresses" in Chapter 2. - fname
MCU only. The file name of the NM user library. Since multiple NM libraries can be bound
with the XL= option on a RUN command,
:run nmprog; xl=lib1,lib2.testgrp,lib3
|
it is necessary to specify the desired NM user library. For example:
MCU lib1 204c
MCU lib2.testgrp test20+1c0
|
If the file name is not fully qualified, the following defaults are used: Default account: the account of the program file. Default group: the group of the program file.
- cmabsaddr
MCA, MCAX only. A full CM absolute code address specifies three necessary items: Either the CST or the CSTX. The absolute code segment number. The CM word offset within the code segment.
Absolute code addresses can be specified in two ways: As a long pointer (LPTR): - MCA 23.2644
Implicit CST 23.2644 - MCAX 5.3204
Implicit CSTX 5.3204
As a full absolute code pointer (ACPTR): - MCA CST(2.200)
Explicit CST coercion - MCAX CSTX(2.200)
Explicit CSTX coercion - MCAX logtoabs(prog(1.20))
Explicit absolute conversion
The search path used for procedure name lookups is based on the
command suffix letter: - MCA
GRP, PUB, LGRP, LPUB, SYS - MCAX
PROG
- virtaddr
MV only. The virtual address to be modified. Virtaddrcan be a short pointer, a long pointer, or a full logical code pointer. - realaddr
MZ only. The real mode memory address to be modified. - ldev.off
MSEC only. The logical device number (LDEV) and byte offset
of the data on disk to be displayed. This address is entered in the form ldev.byteoffset. - count
MA, MC, MD, MDB, MS, MQ: The number of CM 16-bit words to be modified. MC, MV, MZ: The number of NM 32-bit words to be modified. If omitted, a single line of values is modified. - base
The desired representation mode for output values: - % or OCTAL
Octal representation - # or DECIMAL
Decimal representation - $ or HEXADECIMAL
Hexadecimal representation - ASCII
ASCII representation
This parameter can be abbreviated to as little as a single character. If omitted, the current output base is used. - newvalue(s)
The new values for the specified locations. Specified new values are
automatically assigned to the locations until the new values are exhausted. If the new values are omitted, or if they run out, Debug prompts for the remaining new values. To retain the original value, simply press Return. The character dot "." can be entered to abort the modification loop. All locations modified before the dot is encountered are permanently changed.
Examples | |
$nmdebug > mv sp-2c,,,4
$ Virt 21.40050780 = '....' $e7 := 4
|
Modify value at SP-2c, replacing it with $4.
%cmdebug > md 1.64,6,h
$ DST 1.34 = "v4" $7634 := %111
$ DST 1.35 = ".." $5 := (retain original value)
$ DST 1.36 = ".." $fffa := $c0
$ DST 1.37 = ".." $fff0 := 1234
$ DST 1.38 = ".." $0 := .
current/remaining modifications aborted at user request
|
Modify 6 words starting at DST 1.64. Display values (and addresses) in hex. DST 1.34 is assigned a new value of %111. DST 1.35 retains its original value of %5. DST 1.36 is assigned a new value of $c0. DST 1.37 is assigned a new value of 1234. Dot "." terminates modifications.
The modifications for DST 1.34 through 1.37 have been successfully completed.
%cmdebug > mq-30,6
% Q-30 = ".P" %27120 := "AB"
% Q-27 = "UB" %52502 := 'CD'
% Q-26 = ".S" %27123 := u16("EF")
% Q-25 = "YS" %54523 :=
% Q-24 = ".." %177772 := [q-2]
% Q-23 = ".." %7 := !s + (1000-[db+22]/2)
|
Modify 6 words starting at Q-%30. The current values are displayed in ASCII and octal (current output base). Q-30 is assigned the (implicitly coerced) integer value of "AB". Q-27 is assigned the implicitly coerced) integer value of 'CD'. Q-26 is assigned the explicitly coerced unsigned 16-bit integer value of "EF". Q-24 is assigned the contents of Q-2. Q-23 is assigned the value of the S register + ( 1000 - the contents of DB+22 divided by 2).
|
